


A Sliver of Infinity

by realisticallycynical



Category: Haikyuu!!
Genre: Anxiety, Childhood Friends, Double whammy, Emotional Hurt/Comfort, Fluff, Friends to Lovers, Growing Up Together, Kuroo Tetsurou is a Good Friend, M/M, Separation Anxiety, Slice of Life, Social Anxiety, and, but it's not too graphic dw, how haven't i written for these two before i love them a lot, they've just. appeared in other things, why didn't they get their own fic
Language: English
Status: In-Progress
Published: 2018-03-20
Updated: 2018-03-20
Packaged: 2019-04-05 00:35:35
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,063
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14032281
Author URL: https://archiveofourown.org/users/realisticallycynical/pseuds/realisticallycynical
Summary: They’re young when they meet.Too young for Tetsurou to be the social butterfly he would be later, for Kenma to have beaten more than two games. Too young for Tetsurou to have built up his mask, and too young for Kenma to have developed the contradictions that would later play such a big part in their lives.Young enough to still be separate entities.--A story of forever, in little moments in time





	A Sliver of Infinity

**Author's Note:**

> me: i'm gonna work on my WIP and finally update
> 
> kuroken: *exists*
> 
> me: ok you've convinced me

They’re young when they meet. 

Too young for Tetsurou to be the social butterfly he would be later, for Kenma to have beaten more than two games. Too young for Tetsurou to have built up his mask, and too young for Kenma to have developed the contradictions that would later play such a big part in their lives. 

Young enough to still be separate entities. 

Tetsurou is sitting on the swing in the park, occasionally kicking his legs a little to keep himself moving-- because, he reasons, what's the point in being on a swing if he's not moving at all? --and watching the kids on the jungle gym playing with their parents chatting amicably on the benches. It's not unusual either; Tetsurou is almost a pro at this. He spends a lot of time at this park, on this swing. He's taught himself all sorts of tricks on the thing, and come home with skinned knees and pinched fingers more times than he can count. 

Not for the first time, he considers going over and asking if he can play. 

They'll probably say yes, he knows. Even if it's only so their parents don't scold them for being rude, the other kids will let him play if he asks. It's the asking that's the issue though, so he sits. And he swings. 

He swings aimlessly for a bit and wonders what it's like to be one of the kids that doesn't want school to start already. 

It's only when he starts twisting the swing's chains together that Tetsurou sees him. 

The kid is sitting up against a tree, in one of the more secluded areas of the park. His dark hair falls in front of his face, obscuring Tetsurou's view of his face, and there's a gameboy in his hands. 

After a long moment, Tetsurou decides to go for it. Why not? he thinks. Worst case scenario, the kid hates him and Tetsurou goes back to his swing alone.

...actually, that sounds kind of awful. 

Still, he's already on his feet and his carefully twisted swing chains are clattering against each other as they unravel and separate, the way they were meant to be. 

So he plasters a smile on his face-- the one that actually makes him seem approachable when he can make himself talk to other people --and marches over to the kid. He pauses his game when Tetsurou's shadow falls on him, blocking the sun, but doesn't look up.

"I've never seen you here before," Tetsurou says. 

There's a long moment of silence. Tetsurou feels a little like he's just been punched in the gut when the boy looks up and blinks at him with wide, golden eyes before looking back down. 

"I just moved," the kid says. His voice is thin and whispery, and Tetsurou has to stop himself from asking him to speak up. 

Instead he beams, because someone new to the neighborhood means someone he might be able to make friends with outside of school. "That's so cool! I never lived anywhere but Tokyo, it must be so cool to travel like this."

The kid just shrugs. His fingers twitch and grip his gameboy tighter, so Tetsurou switches topics. 

"What are you playing?" 

It takes another moment for the kid to answer, which Tetsurou thinks might be a normal thing. But he does answer, which is still better than being on the swing. 

"Just Pokemon," the kid says.

Tetsurou smiles for real this time. "I love Pokemon! Can I pl-- watch you play?"

At that, the kid looks up. His eyes flicker over to the parent benches and back to Tetsurou and he cocks his head, considering something that Tetsurou can't even begin to guess at. Then he nods and scoots over just a few inches to make room. The boy's name is Kozume Kenma, he learns. 

A gust of wind blows hard and across the playground, an empty swing flips around, its chains twisting together. 

****

Tetsurou, despite being the one to try to make friends, doesn't anticipate growing as attached as he does to Kenma. 

They spend nearly every day at the park together now, playing Pokemon and Zelda and Kirby together. Occasionally, if Kenma is in a particularly good mood, Tetsurou will be able to coax him away from the tree so they can play something that doesn't have a screen. 

It's volleyball the day Tetsurou is invited to spend the night at Kenma's house. 

Kenma looks about five "one more toss" pleas from ending Tetsurou's life then and there, but Tetsurou just laughs. Kenma gets annoyed easily, but if he was really dead set against this he would sit his butt on the ground and refuse to even look at the ball. He's stubborn that way, Tetsurou is learning. 

Someone calls his name-- Kenma's, that is. Tetsurou's parents don't come with him to the park very often, but Kenma's always do. Tetsurou can't help but be a little jealous sometimes.

"Kenma, it's time to go. Have you asked him yet?" His mother snaps her purse shut.

Kenma shakes his head obediently and looks at Tetsurou. "My parents and I were wondering if you wanted to spend the night at our house tonight."

The words sound almost rehearsed with how stiff they are, and Tetsurou tries hard not to wince. Kenma's entire demeanor tends to change when he knows his parents are listening. Tetsurou can't tell why it bothers him so much.

Still, he's excited at the question even despite his discomfort. 

"If it's not too much trouble. My mom probably won't mind," he says. It's not technically a lie, since he somehow doubts whether his parents will even notice his absence through all the yelling. "I would have to go home and get clothes though."

Kenma's eyes sharpen and Tetsurou has the distinct feeling he's being examined. For what, he can't even begin to know. Still, he doesn't say anything, instead nodding and repeating what Tetsurou said to his mother. 

"Of course," she says warmly, smiling at Tetsurou. "We can wait here for you or give you a ride home if you want, Tetsu-chan. You live around here, right?"

Tetsurou nods, wringing his hands. "It won't take long for me to get back, if you're sure you're alright waiting, Kozume-san. I could just walk to your house too, if it's too much trouble."

Golden eyes are burning a hole into the side of Tetsurou's head, but Kenma says nothing. 

It takes a lot of roundabout convincing from Tetsurou, but he manages to talk Kozume-san out of driving him home so he can pick up his clothes. She finally agrees to wait at the convenience store on the corner as a compromise.

It's less than a five minute drive, but Kenma is staring at Tetsurou the entire time, making it seem infinitely longer. 

Tetsurou dashes down the street and slips into his house through the back door. Dad is asleep on the couch and it doesn't look like Mom has gotten home yet, so he scrawls a note to her and sticks it to the fridge, conspicuously next to the drawing he gave her for Mother's Day. 

He shoves some pj's and clothes into his bag, and grabs some toiletries before slipping out the back door just as quietly as he entered. This time he locks it behind him. He doesn't think he's ever been in and out of his house so fast, he realizes as he reaches the car at the end of the block. 

Kenma blinks at him, but is still eerily silent. His mother turns on the radio as they drive, and makes small talk with Tetsurou. 

Their house, it turns out, is within walking distance from his own. Tetsurou has the feeling, as Kenma leads him up to his bedroom to play videogames until dinner, that that’s going to be incredibly convenient in the future. After all, Kenma is already basically his best friend. 

 

By the time school starts up again, Tetsurou is spending much more time with Kenma than he is at home. Whether they’re at the park or the arcade or Kenma’s house, the two of them are together nearly every day. 

Kenma's mom, Tetsurou has learned, will let Kenma out to do almost anything if Tetsurou is there. As nice as she is though, Tetsurou still prefers hanging out with Kenma alone. 

With Kenma he's  _ Kuro _ , and not Tetsurou or Kuroo-kun or Tetsu-chan or whatever it is that the adults have decided to call him that day. And for some reason, the distinction seems important. 

"Kuro, you're losing." Kenma is annoyed. 

Kuro snaps out of it and gets his head back in the game. He's probably going to lose anyway; Kenma is almost unbeatable in Galaga. Besides, they have plenty more quarters for the day. It's the last day before the end of break, and Kuro's been saving up. He's been planning today for weeks, since it'll be his last day with Kenma to himself. They’re going to spend all day at the arcade, and they're going to go get ice cream afterward and go to Kenma's house for the night and walk to school together in the morning. 

They're going to the same elementary school, but it'll be a  _ whole school year _ before they'll be able to hang out all day, every day. Besides, there's no way Kenma isn't going to be popular here, he's too cool.

And everything goes well today, Kuro thinks. Kenma beat him soundly at almost every game, but Kuro managed to hold his own a few times, much to the younger boy's frustration. The ice cream woman gave them their scoops for free, cooing over how cute they were together (which was irritating, but Kuro couldn't blame her; Kenma is adorable when he sees something he wants).  

Kozume-san made a special dinner because it's the night before Kenma's second year and Tetsurou's third year of elementary school and "isn't that worth celebrating, Tetsu-chan?"

Tetsurou doesn't know, but he nods anyway. Kozume-san seems satisfied and Kenma eats his food quietly. 

It's only when they're in bed that Kuro notices that something is off. 

He's asleep when he hears it-- or rather, it's like he senses it, because Kenma is a quiet person, is almost always a quiet person. Kenma's ragged breathing echoes oddly through the room, and when Kuro opens his eyes, there's light coming from the bathroom. 

"Kenma?" Kuro picks himself up off the futon and manages to put one foot in front of the other without tripping on any of Kenma's things or his own exhaustion. "Kenma, are you ok?"

The breathing gets even quieter, now that Kenma knows he’s awake. When Kuro pushes the door open, he’s scrubbing at his face harshly.

Kuro can’t help but freak out a little bit. Kenma doesn’t cry, ever. The only time he’s ever seemed close was that time he got his fingers pinched in the chains of Tetsurou’s swing. But now, in the middle of the night, he’s scrubbing his face clean of old tears even as new ones fall to replace them. 

“Oh no, don’t cry Kenma, did you…” Kuro wants to ask if he somehow got hurt, or if something happened, but that would be dumb. Kenma was in  _ bed, _ what could have happened to him? So he flounders helplessly for a second.

Then he holds open his arms. He doesn’t expect anything, since Kenma usually ducks away from his hugs or hair ruffles, but it’s all he can think of. 

It catches him completely by surprise when Kenma all but falls into his arms and clutches his shirt, but he figures that at least now he sort of knows what to do. He can do hugs, he thinks, leaning back against the bathroom wall. Kenma is getting saltwater and snot all over Kuro’s pajamas, but he thinks he’ll get over it. Just this once. 

It’s a long time before Kenma cries himself out, but he does. He gets to his feet shakily, never letting go of Kuro’s shirt. Kuro is too sleepy to do much other than follow Kenma back to his bedroom.

Only when he wakes up too-warm with hair in his face and a shirt stiff from grime does he realize that he never went back to his futon. 

After that day, he never does.

Kuro is in his element in school. He’s got friends he talks to sometimes, and he’s generally well-liked by his classmates. His teachers adore him, so he gets away with little things that most other kids wouldn’t. 

Before, that’s not something he would have taken advantage of. Now that Kenma is part of his new normal, he does bend the rules from time to time. 

It takes more than a year for Kuro to realize that Kenma sees the world differently. Not just differently from him, but from most of the world. 

Kuro knows the world isn’t black and white, the way they’re taught in school. People aren’t all good or all bad. His mom isn’t all good, and his dad isn’t all bad. Even Kenma has his faults, though he’s as close to perfect as anyone Kuro has ever met. He read in a poem once that life exists in shade of grey.

But Kenma… Kenma sees the world in color. 

He spends so much time watching that he sees things Kuro can never hope to. He’s smarter than a kid younger than Kuro has any right to be, and he  _ sees. _ It’s so cool to see when it’s not Kuro he’s watching, when they’re out for ice cream or sitting in the park after school. It’s only when Kuro goes to middle school and Kenma is forced to stay behind that he realizes something crucial.

For all that Kenma sees the world in bright, blinding technicolor, he sees himself in a dull grey. 

And Kuro isn’t as surprised as he should be to realize that, to him, Kenma is the only person who isn’t. 

Tetsurou-- always, always Tetsurou, only really Kuro to Kenma --joins the volleyball club in his first year as a middle schooler, and he loves it. He loves being a wing spiker, and loves making more friends outside of his class.

The kids at school come to their games, and they cheer for him when he scores a point. He likes how it feels to be a part of something bigger than himself, how it feels to revel in victory and weep at failure when it means more than it would alone. 

Tetsurou joins the volleyball club. He takes to middle school like a duck to water, getting top marks and making friends and even getting confessed to once or twice. He loves it, loves that he’s able to be social like this now. 

He also hates it, just a little. 

He hates that, after school, he’s walking alone to a home he doesn’t want. Hates that the spikes he’s hitting don’t fit right in his hand, that they don’t land where they’re supposed to. Hates that he has a cell phone now, with enough phone numbers in it to keep him busy, but the one person whose number he’d  _ like _ to have doesn’t have a phone yet. 

He hates that he’ll make a stupid, awful joke and turn around only to be met with emptiness where narrowed golden eyes should be.

“I miss you,” Kuro murmurs into Kenma’s hair one weekend, during one of their sleepovers. It’s the middle of the night, too late for either of them to be up, but they are and Kuro is saying stupid things that have no business being said. 

Kenma doesn’t say a word, only presses his face into Kuro’s neck. Kuro doesn’t mind; it’s Kenma’s way of saying  _ I miss you too. _

It’s a bittersweet year where the sweet is saccharin and the bitter is poison. 

(For Kenma, Kuro would realize later, it’s even worse.)

Next year is better. Kuro-- and it’s so nice to go back to Kuro, to having someone around who doesn’t pander to Tetsurou for one reason or another and sees him for who he is --isn’t able to get Kenma to join the team, no matter how much he whines. He does manage to needle him into showing up to practices as a spectator, his PSP in hand, and Kuro finds he’s alright with that. It means they get to walk home together again. 

And if he manages to get Kenma to send him a few extra tosses after practice once in a while, well. That’s just a bonus.

Which isn’t to say that middle school is perfect just because Kenma is there, far from it. Middle school is hellish for other reasons, things that the two of them can’t control.

There are a few things Tetsurou doesn’t think about very often, unless they relate to Kenma. Other kids’ tendency to gossip is among them. After all, Tetsurou hasn’t often been the subject of rumors in his life. 

But the simple fact of the matter is that Tetsurou is popular, and Kenma is not. It’s almost by design; Tetsurou pulls in attention to keep it away from Kenma. He doesn’t mind having positive attention for once, and Kenma prefers settling comfortably in the shadow he creates. 

And the other kids at school don’t seem to know what to do with the slightly different Tetsurou that appears when Kenma is around. So they do what kids do: they wonder, and they talk.

No one is brave enough to say it to Tetsurou’s face, and no one is stupid enough to say it to Kenma, but the whispers in the halls speak for themselves. People either think being friends with Kenma is Tetesurou being too nice, or being cruel by pretending to be friends with the weird first year. They can’t figure out that Kenma gives as much as he gets in their friendship. Middle school in Tokyo is based around fitting in, sticking with a certain group who acts a certain way, and Tetsurou doesn’t fit that mold anymore; in their minds, there has to be a reason.

It boils Kuro’s blood, but he knows better. He doesn’t bring it up to Kenma, and neither of them ever addresses the rumors. 

At least, not outright. Kenma tries to pull away in his second year, Kuro’s third. He does it quietly, does it so slowly that Kuro, had it been anyone else, wouldn’t have even noticed. But it’s Kenma, and because it’s Kenma, of course he notices. 

He doesn’t allow it, but he doesn’t make it a  _ thing _ either. When Kenma brushes him off in school, he makes more of an ass of himself than usual so they just draw even more attention. When he leaves without making plans, Kuro sends him texts pestering him about little things. 

“You’re acting like a neglected boyfriend,” Kenma mentions offhandedly one day when they walk home. 

It hits a little harder than Kuro wants to admit, but he just shrugs. “You’ve been acting suspicious.”

“You have other friends.”  _ You have better friends,  _ he’s saying.  _ You don’t need me anymore. _

“Yeah, but I don’t have another you.” 

It’s not all that needs to be said, Kuro suspects. Not by a long shot. There’s something he’s not saying that he doesn’t have the words for right now. But it seems to be enough for now. They sit on the swings in the nearly deserted park and, for a while, it’s like they’re little kids again. 

  


Kenma doesn’t come to Kuro’s house often, and never overnight. There have been a few times when they’ve made a stop there to pick up something, but Kuro can count on one hand the number of times Kenma has been in his room for longer than ten minutes. 

Kuro has never outright said why he doesn’t like being home, but after all this time there’s no way Kenma doesn’t know. So they hang out exclusively at Kenma’s house even though his parents are too strict and too invested in their friendship. 

It works out; Kuro is able to live out some semblance of normalcy, and Kenma has someone to stop him when he either works himself into the ground or gives up entirely. 

But at the end of the day, at the end of the weekend, at some point, Tetsurou goes home. It’s inevitable. For all that their lives twist into each other’s tightly, there are still some parts that don’t fit together. And Kenma will never fit into this part of Tetsurou’s life if he has anything to say about it. Some things, Tetsurou knows, are better separate, and he does his damndest to keep it that way.

It’s Kuro’s fault when it all comes down around him.

Since Kenma got a phone in year one, Kuro hasn’t stopped blowing it up. Pictures of stray animals he finds on his way home, stupid texts in the middle of the night when he can’t sleep, regular check-in texts on bad days. It doesn’t change on days when one of them is sick-- in fact, it gets worse. They see each other all the time, and talk even more. Which is why Tetsurou doesn’t know how he could have screwed up so badly.

He tells his mom to go to work the day after Dad leaves. She tries to stay home for him, not herself, and Tetsurou knows it’ll just be worse that way so he promises her that he’ll call if he needs anything and all but shoves her out the door. 

Both Tetsurou and his mother were awake last night. It was cold, he remembers; his window was open. Tetsurou watched his parents’ last fight from a crack in his bedroom door, tired to the bone after a sleepless night the night before and a grueling volleyball practice, but unable to sleep. It’s only once he’s alone in his house for the first time in months does the exhaustion of being awake for forty eight hours hit. 

Tetsurou collapses on the couch and falls asleep instantly.

His dreams are disjointed, made up of cold, terrifying half-images that seem to take forever to end, but they do end.

The sound of quiet clicking is all Tetsurou hears when he wakes up. Someone’s draped a blanket over him, he realizes, blinking blearily. It’s almost dark out, but there’s enough light for him to make out the back of a head of dark hair a few inches away and the familiar glow of a PSP screen.

“You weren’t answering your phone and your window was open. You come in through mine all the time--” Kenma starts to explain, but stops when Kuro leans his head on his shoulder and lets out a breath. 

Kenma is here. Of course Kenma is here, Kuro was stupid to think he wouldn’t be, eventually. He’s never been more glad to be wrong about something before. 

It’s not the first time Kenma has ever taken care of him, and it won’t be the last. He puts something cold into Kuro’s lap-- one of those prepackaged convenience store meals --and crawls up on the couch, curling into Kuro’s side. 

“Whatever it is that’s got you like this, you’re not sick so you’re gonna eat that.” He only unpauses his game when Kuro opens the packaging and settles into a more comfortable position to watch him play.

He’s still hurting over what happened. He’s still a little lost, a little relieved, a little guilty over something that he knows isn’t his fault. And Kenma doesn’t know why but he’s still here. 

Kuro will tell him tonight, when they’re both pretending to sleep for each other’s benefit. He’ll whisper every doubt, every insecurity into Kenma’s hair and it will be alright, in the darkest hour of the night, for him to cry. And Kenma will do the same, whispering almost inaudibly about how much he’s dreading dealing with school without Kuro again next year. 

But for now, he’s alright with the way things are. He’s warm, Kenma is curled into his side, and his house is quiet for the first time in years. 

Kuro’s mother walks in on them like that, dozing now that Kenma’s PSP is finally dead, and silently goes to put out a futon that neither of them is going to use. 

**Author's Note:**

> ch 1 was primary and middle school
> 
> ch 2 will be high school, college, and maybe beyond


End file.
